Year Percent 1997-01-01 0.52120600000000010 1998-01-01 0.21655100000000002 1999-01-01 0.13358399999999998 2000-01-01 0.38318000000000000 2001-01-01 2.97812000000000000 2002-01-01 1.43523000000000000 2003-01-01 2.47734000000000030 2004-01-01 2.35072000000000000 2005-01-01 2.65134000000000030 2006-01-01 2.76085000000000000 2007-01-01 3.05780000000000000 2008-01-01 3.58905000000000000 2009-01-01 3.60324000000000000 2010-01-01 3.60848000000000000 2011-01-01 2.98247000000000000 2012-01-01 1.78977000000000000 2013-01-01 1.62880000000000000 2014-01-01 1.84969000000000000 2015-01-01 1.88854000000000000 2016-01-01 1.37305000000000000